Fructose oligosaccharides have nutritional advantages in animal and human diets. These oligosaccharides modify intestinal bacteria and in particular are effective in increasing the proportion of bifidobacteria in the digestive tract of animals. Thus, caramels containing a high proportion of fructose oligosaccharides are more nutritional.
Caramels are products obtained by heating carbohydrates such as sucrose, glucose or other reducing sugars. Typically, the carbohydrates may be heated either dry or with water, either alone or after addition of acid or base or nitrogen compounds, and in a batch or continuous process. The time generally required to achieve caramelization is several hours, typically from 3 to 9 hours.
The composition of caramels has been studied previously and caramels prepared from sucrose have been shown to contain small amounts of oligosaccharides, predominantly glucose disaccharides.
Canadian Patent No. 733,457 is directed to a continuous process of producing caramelization by heating an aqueous fluid of sucrose and citric acid to a temperature of 120.degree.-150.degree. C. in a heat exchanger under pressure for approximately 1-10 minutes. However, there is no disclosure that the sucrose and citric acid are to be milled for several hours prior to heating.
U.S. Pat. No. 2,594,538 also discloses a method of making caramel from sucrose and orange juice acid (citric acid) by heating at a temperature of preferably 120.degree. C. The patent does not disclose mixing the reactants in a mill prior to heating.
Heretofore there has not been a method for producing caramel compositions containing fructose oligosaccharides. Thus, a need exists for the preparation of caramel which contains a high content of fructose oligosaccharides.
According to the present invention, it has been discovered that a unique caramel product may be prepared having a high content of fructose oligosaccharides wherein a mixture of sucrose and an organic acid is pulverized to a finely divided mixture prior to thermolysis. The pulverized mixture is subsequently heated at a temperature of about 5.degree. to 25.degree. C. above the melting point temperature of the mixture for approximately 0.5 to 30 minutes, preferably 0.5 to 15 minutes, and cooled rapidly. The caramel product formed contains a high proportion of fructose oligosaccharides.